The leveling and alignment process of the ballastless track today is a manual, very little automated process, which is carried out by making successive approximations, and that requires successive topographical checks by measurement equipment and external topography staff, who should be measuring and transmitting the position that the rails will be acquiring during the process so that this can be corrected through the usual procedure using jacks, aligner or leveler spindles, until finally reaching the definitive position.
That is, starting with a first approximation lift, and after the corresponding external topographic checking of the achieved position, the information obtained from the measurement carried out must be transmitted by topography staff to the staff in charge of the physical positioning of the track, point at which the position can be manually corrected and checked again, and so forth until it is verified that the position of the track is within the required tolerances, point at which, after firmly fixing the position, it can be concreted.
The position of the rails is usually measured using a topographic station and a prism supported by an operator on the active side of the rail—being able to use in addition a cant straightedge—, or through the use of a track auscultator cart, or using a mixed topographic system between both options.
An alternative to this process, which is also commonly used, consists of the previous marking in fixed references of the final position at every certain length of track. In this case, the topographic work is carried out in advance, and the approach to the final position marked on each section of track is done by reference to those previously marked data making successive manual checks.
These methods, as well as other existing methods, all of them manual and no automated, imply that the current process is extremely slow and has a high cost.